1. Field of the Invention
The present invention relates to a portable telephone set and a window switching control method used therefor and, more particularly, to window display switching control on a portable telephone set used for a mobile communication system.
2. Description of the Prior Art
A conventional portable telephone set is designed to display a standby window, a termination window, a schedule notification window, a menu window, various setting windows, and the like. Functions corresponding to these windows, i.e., a standby function, a termination function, a schedule notification function, a menu function, various setting functions, and the like, render the corresponding windows.
Recently, a portable telephone set has been equipped with additional functions such as an electronic mail function and Internet site (content) display function, and its various functions have improved. With this improvement, the number of corresponding windows has also increased. The above functions are implemented by application programs stored in the portable telephone set.
In the above conventional portable telephone set, windows corresponding to various functions are asynchronously displayed. If an incoming call is received while the window corresponding to the schedule notification function, menu function, or electronic mail input function is displayed, a plurality of keys must be operated to switch the window to the window corresponding to the termination function (e.g., a window for displaying originator information), and complicated control is required to prevent a conflict between window control operations based on key operation and the like.
Conventionally, each of the above functions renders a corresponding window. However, each function cannot be separated from the remaining functions because of consideration given to rendering operations performed by the remaining functions. In this case, the use of the Window System makes it possible to maintain the independence of each function window. However, this requires an increase in memory capacity and complicated window switching control.